WASHINGTON (CNN) -- When U.S. officials spoke in the past of the need for North Korea to declare the extent of its nuclear program, everyone from President Bush down said it must be "complete" and "verifiable."

The cooling tower was demolished Friday at the Yongbyon nuclear complex in North Korea.

But since Pyongyang released details of its program last week, U.S. officials aren't using the word "complete" any longer.

"We think that this declaration is verifiable," State Department spokesman Sean McCormack said Wednesday. He declined to say whether it was "complete."

On June 26, North Korean officials turned over to China a 60-page declaration, written in English, that details several rounds of plutonium production at the Yongbyon plant dating back to 1986.

In the report, North Korea acknowledges producing roughly 40 kilograms of enriched plutonium -- enough for about seven nuclear bombs, according to the U.S. State Department.

But the document doesn't detail North Korea's suspected uranium enrichment program or its nuclear cooperation with Syria. In an addendum to the document, North Korea acknowledges those concerns and says it will cooperate to work out differences to mutual satisfaction.

On Tuesday, U.S. envoy Chris Hill, who has led the U.S. delegation at the six-party talks, said the declaration is a good first step.

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The Bush administration is stressing the ability to verify North Korea's claims on its nuclear past rather than publicly shame them, officials have said, noting that North Korea has already handed over 19,000 documents on its nuclear history.

Hill said it was significant that last year North Korea was producing plutonium but isn't able to any longer because it has disabled its reactor.

For months, North Korea has been disabling its nuclear facility at Yongbyon under the watchful eyes of representatives of the five other nations, including the United States, that have been involved in talks aimed at ending Pyongyang's nuclear weapons program.

On Friday, North Korea destroyed a water cooling tower at the facility, where officials acknowledge they extracted plutonium to build nuclear weapons. McCormack said the United States paid North Korea roughly $2.5 million to implode the cooling tower.

During negotiations, the United States softened demands that North Korea admit in the declaration to having a highly enriched uranium program and supplying Syria with nuclear technology -- sticking points that had stalled the talks for months.

U.S. officials said the final deal isn't perfect, but it offers the United States its best chance yet to learn about North Korea's nuclear activities, and officials say that is more important than having North Korea publicly admit to the uranium or proliferation activities.

In response to North Korea's declaration and its disabling of Yongbyon, Bush said he would lift some U.S. sanctions against North Korea and remove the country from the State Department's list of state sponsors of terrorism.

In doing so, he said, there are still "a number of issues of serious concern to the United States and the international community."

"To end its isolation, North Korea must address these concerns. It must dismantle all of its nuclear facilities, give up its separated plutonium, resolve outstanding questions on its highly enriched uranium and proliferation activities, and end these activities in a way that we can fully verify," Bush said.